If mlock is required either due to use of VFIO hostdevs or due to the
fact that it's enabled it needs to be tweaked prior to adding new memory
or after removing a module. Add a helper to determine when it's
necessary and reuse it both on hotplug and hotunplug.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1273491

New function qemuDomainGetMlockLimitBytes will now handle the
calculation so that it unifies the logic to one place and allows later
reuse.

The code reported that a migration flag is unsupported but didn't jump
to the error label. Probably an oversight in commit f88af9dc that
introduced the flag checking.

Since the flag was not enabled when 'eating' the migration cookie,
libvirt reported a bogus error when memory hotplug was enabled:

 unsupported migration cookie feature memory-hotplug

The error was ignored though due to a bug in the code so it slipped
through testing.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1278404

nodeset should be freed in both success and failure paths.

While tmppath is freed immediately after it's consumed, moving it from
error to cleanup label is a bit more consistent and robust.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Remove code duplication by moving common cleanup code in a dedicated
label.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Generally, we use "ret" variable for storing the value we are going to
return at the and of a function, but this is not the case in
qemuProcessStart. Let's rename "ret" as "rv".
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Current "cleanup" label is only used in error path, thus it should
rather be called "error".
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

qemuProcessStart was passing char * migrateFrom as the third argument to
qemuPrepareNVRAM. We should explicitly convert the pointer to bool which
is what the function expects.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1270715

Commit id '9deb96f9' removed the code to fetch the nodeset from the
CpusetMems cgroup for a running vm in favor of using the return from
virDomainNumatuneFormatNodeset introduced by commit id '43b67f2e'.
However, that API will return the value of the passed 'auto_nodeset'
when placement is VIR_DOMAIN_NUMATUNE_PLACEMENT_AUTO, which happens
to be NULL.

Since commit id 'c74d58ad' started using priv->autoNodeset in order
to manage the auto placement value during qemuProcessStart, it should
be passed along in order to return the correct value if the domain
requests the auto placement.
Signed-off-by: NLuyao Huang <lhuang@redhat.com>

In commit f41be296, we moved vm->persistent check into
qemuDomainRemoveInactive, but we didn't change the vm->persistent
before call qemuDomainRemoveInactive in some place before and just
call it to remove the inactive vm.
Signed-off-by: NLuyao Huang <lhuang@redhat.com>

This calls the PCI-, USB- and SCSI-specific functions just
like qemuHostdev{Prepare,ReAttach}DomainDevices() already do,
and was the missing piece for the qemuHostdev API to nicely
mirror the virHostdev API.

Update qemuProcessReconnect() to use the new function.

Adopt the same names used for virHostdevUpdateActive*Devices() for
consistency's sake and to make it easier to jump between the two.

No functional changes.

Adopt the same names used for virHostdevReAttach*Devices() for
consistency's sake and to make it easier to jump between the two.

No functional changes.

Adopt the same names used for virHostdevPrepare*Devices() for
consistency's sake and to make it easier to jump between the two.

No functional changes.

We have macros for both positive and negative string matching.
Therefore there is no need to use !STREQ or !STRNEQ. At the same
time as we are dropping this, new syntax-check rule is
introduced to make sure we won't introduce it again.
Signed-off-by: NIshmanpreet Kaur Khera <khera.ishman@gmail.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Tunnelled migration can hang if the destination qemu exits despite all the
ABI checks. This happens whenever the destination qemu exits before the
complete transfer is noticed by source qemu. The savevm state checks at
runtime can fail at destination and cause qemu to error out.
The source qemu cant notice it as the EPIPE is not propogated to it.
The qemuMigrationIOFunc() notices the stream being broken from virStreamSend()
and it cleans up the stream alone. The qemuMigrationWaitForCompletion() would
never get to 100% transfer completion.
The qemuMigrationWaitForCompletion() never breaks out as well since
the ssh connection to destination is healthy, and the source qemu also thinks
the migration is ongoing as the Fd to which it transfers, is never
closed or broken. So, the migration will hang forever. Even Ctrl-C on the
virsh migrate wouldn't be honoured. Close the source side FD when there is
an error in the stream. That way, the source qemu updates itself and
qemuMigrationWaitForCompletion() notices the failure.

Close the FD for all kinds of errors to be sure. The error message is not
copied for EPIPE so that the destination error is copied instead later.

Note:
Reproducible with repeated migrations between Power hosts running in different
subcores-per-core modes.
Signed-off-by: NShivaprasad G Bhat <sbhat@linux.vnet.ibm.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1249981

When qemuDomainPinIOThread was added in commit id 'fb562614', a check
for the IOThread capability was not needed since a check for iothreadpids
covered the condition where the support for IOThreads was not present.
The iothreadpids array was only created if qemuProcessDetectIOThreadPIDs
was able to query the monitor for IOThreads. It would only do that if
the QEMU_CAPS_OBJECT_IOTHREAD capability was set.

However, when iothreadids were added in commit id '8d4614a5' and the
check for iothreadpids was replaced by a search through the iothreadids[]
array for the matching iothread_id that left open the possibility that
an iothreadids[] array was defined, but the entries essentially pointed
to elements with only the 'iothread_id' defined leaving the 'thread_id'
value of 0 and eventually the cpumap entry of NULL.

This was because, the original IOThreads commit id '72edaae7' only
checked if IOThreads were defined and if the emulator had the IOThreads
capability, then IOThread objects were added at startup. The "capability
failure" check was only done when a disk was assigned to an IOThread in
qemuCheckIOThreads. This was because the initial implementation had no way
to dynamically add IOThreads, but it was possible to dynamically add a
disk to the domain. So the decision was if the domain supported it, then
add the IOThread objects. Then if a disk with an IOThread defined was
added, it could check the capability and fail to add if not there. This
just meant the 'iothreads' value was essentially ignored.

Eventually commit id 'a27ed6e7' allowed for the dynamic addition and
deletion of IOThread objects. So it was no longer necessary to generate
IOThread objects to dynamically attach a disk to. However, the startup
and disk check code was not modified to reflect this.

This patch will move the capability failure check to when IOThread
objects are being added to the command line. Thus a domain that has
IOThreads defined will not be started if the emulator doesn't support
the capability. This means when qemuCheckIOThreads is called to add
a disk, it's no longer necessary to check the capability. Instead the
code can use the IOThreadFind call to indicate that the IOThread
doesn't exist.

Finally because it could be possible to have a domain running with the
iothreadids[] defined prior to this change if libvirtd is restarted each
having mostly empty elements, qemuProcessDetectIOThreadPIDs will check
if there are niothreadids when the QEMU_CAPS_OBJECT_IOTHREAD capability
check fails and remove the elements and array if it exists.

With these changes in place, it turns out the cputune-numatune test
was failing because the right bit wasn't set in the test. So used the
opportunity to fix that and create a test that would expect to fail
with some sort of iothreads defined and used, but not having the
correct capability.

If there are no IOThreads defined, no sense making other checks

Although theoretically both should be the same value, the niothreadids
should be used in favor of iothreads when performing comparisons. This
leaves the iothreads as a purely numeric value to be saved in the config
file.  The one exception to the rule is virDomainIOThreadIDDefArrayInit
where the iothreadids are being generated from the iothreads count since
iothreadids were added after initial iothreads support.

The internal representation of a JSON array counts the items in
size_t. However, for some reason, when asking for the count it's
reported as int. Firstly, we need the function to return a signed
type as it's returning -1 on an error. But, not every system has
integer the same size as size_t. Therefore, lets return ssize_t.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Coverity notices that net->ifname is potentially referenced after a
VIR_FREE().  Since the net->ifname will eventually be free'd during
virDomainDefFree when calling virDomainNetDefFree, let's just that
processing take care the free.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

So imagine you want to crate new security manager:

  if (!(mgr = virSecurityManagerNew("selinux", "QEMU", false, true, false, true)));

Hard to parse, right? What about this:

  if (!(mgr = virSecurityManagerNew("selinux", "QEMU",
                                    VIR_SECURITY_MANAGER_DEFAULT_CONFINED |
                                    VIR_SECURITY_MANAGER_PRIVILEGED)));

Now that's better! This is what the commit does.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Two #define lines introduced by b527aa09 did not respect the
indentation rules, thus breaking syntax-check.

This gets rid of the partially enforced alignment and makes it less
likely for a bogus value to be introduced in the enumeration.
Capabilities are divided in five-element groups for better readability.

Use #define for QEMU_CAPS_NET_NAME and QEMU_CAPS_HOST_NET_ADD, both
of which are aliases for QEMU_CAPS_0_10.

qemuMigrationIsAllowed would disallow offline migration if the VM
contained host devices or memory modules. Since during offline migration
we don't transfer any state we can safely migrate VMs with such
configuration.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1265049

Use the migration @flags for checking various migration aspects rather
than picking them out as booleans. Document the new semantics in the
function header.

Now that qemuMigrationIsAllowed is always called with @vm, we can drop
the @def argument and simplify the control flow.

Additionally the comment is invalid so drop it.

Extract the hostdev check from qemuMigrationIsAllowed into a separate
function since that is the only part that needs to be done in the v2
migration protocol prepare phase on the destination. All other checks
were added when the v3 protocol existed so they don't need to be
extracted.

This change will allow to drop the @def argument for
qemuMigrationIsAllowed and further simplify the function.

Even though QEMU on the source host reports completed migration and thus
we move to the Finish phase, QEMU on the destination host may still be
processing migration data. Thus before we can start guest CPUs on the
destination, we have to wait for a completed migration event.

https://bugzilla.redhat.com/show_bug.cgi?id=1265902Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

With new QEMU which supports migration events,
qemuMigrationCheckJobStatus needs to explicitly query QEMU for migration
statistics once migration is completed to make sure the caller sees
up-to-date statistics with both old and new QEMU. However, some callers
are not interested in the statistics at all and once we start waiting
for a completed migration on the destination host too, checking the
statistics would even fail. Let's push the decision whether to update
the statistics or not to the caller.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

The function already has two bool parameters and we will need to add a
new one. Let's switch to flags to make the callers readable.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

The destination host gets detailed statistics about the current
migration form the source host via migration cookie and copies them to
the domain object so that they can be queried using
virDomainGetJobStats. However, we should only copy statistics to the
domain object when migration finished successfully.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Even if we are migrating a domain with VIR_MIGRATE_PAUSED flag set, we
should still update the total time of the migration. Updating downtime
doesn't hurt either, even though we don't actually start guest CPUs.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

qemu-kvm can be used to run ppc64 guests on ppc64le hosts and vice
versa, since the hardware is actually the same and the endianness
is chosen by the guest kernel.

Up until now, however, libvirt didn't allow the use of qemu-kvm
to run guests if their endianness didn't match the host's.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1267882

Rename the function to virDomainDefCheckDuplicateDiskInfo and make it
check disk serials too.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1245013

Since we'd disallow migration of a guest that would have possibly
invalid config but still be able to work, relax the WWN check to be
performed only on new starts of the VM.

We are using memory-backing-file even when it's not needed, for example
if user requests hugepages for memory backing, but does not specify any
pagesize or memory node pinning.  This causes migrations to fail when
migrating from older libvirt that did not do this.  So similarly to
commit 7832fac8 which does it for
memory-backend-ram, this commit makes is more generic and
backend-agnostic, so the backend is not used if there is no specific
pagesize of hugepages requested, no nodeset the memory node should be
bound to, no memory access change required, and so on.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1266856Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

So since the introduction of the memory-backend-file object until now we
only added '-mem-path' for non-NUMA guests and we used the parameters of
the memory-backend-file object to specify the path to the hugetlbfs
mount.  But hugepages can be also used without memory-backend-file
object, as it used to be before its introduction.  Let's just get this
part of the code back and properly append the '-mem-path' for NUMA
guests as well, but only when the memory backend is not needed.

This parameter is already being applied when no numa is requested and
because we still use memory-object-file unconditionally for
hugepage-backed NUMA guests, this should not fire until later.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

That function is called qemuBuildMemPathStr() and will be used in
other places in the future.  The change in the test suite is proper due
to the fact that -mem-prealloc makes only sense with -mem-path (from
qemu documentation -- html/qemu-doc.html).
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>